I'd love to see it, but I doubt we'll get it. The C7 shows plainly the focus on meeting EPA standards. The equation for more HP in an NA application has been the same for a very long time. A larger camshaft for more air and fuel, better heads to move the air and finally a better flowing exhaust to let it out. The larger camshaft causes issues with emissions and, if large enough, driveability. Consumption will be higher even when not driving aggressively because the valve events will require it.

If we do see a bigger displacement LTx, it will probably be a very mild bump over the LS7 for these reasons. There's no magic wand that is going to make a cam capable of supporting 600+hp be civil enough to market to general public. Even if they could get past the emissions issues.

FI doesn't have a lot of these problems. You don't need a large camshaft, just one patterned for boost. Consumption is comparable when not making boost. Hitting your target output isn't all that difficult. I just wish we would see low mounted turbos from an efficiency and weight balance perspective.

So my guess is if we do see a larger LTx motor it will be a very modest increase over the LS7. Probably 520-530hp. More likely we'll probably get a boosted 600-650hp variant. Or if GM decides they like having 3 price points, two boosted variants. Probably a 550-575hp and 650+hp model.

I'd love to see it, but I doubt we'll get it. The C7 shows plainly the focus on meeting EPA standards. The equation for more HP in an NA application has been the same for a very long time. A larger camshaft for more air and fuel, better heads to move the air and finally a better flowing exhaust to let it out. The larger camshaft causes issues with emissions and, if large enough, driveability. Consumption will be higher even when not driving aggressively because the valve events will require it.

If we do see a bigger displacement LTx, it will probably be a very mild bump over the LS7 for these reasons. There's no magic wand that is going to make a cam capable of supporting 600+hp be civil enough to market to general public. Even if they could get past the emissions issues.

FI doesn't have a lot of these problems. You don't need a large camshaft, just one patterned for boost. Consumption is comparable when not making boost. Hitting your target output isn't all that difficult. I just wish we would see low mounted turbos from an efficiency and weight balance perspective.

So my guess is if we do see a larger LTx motor it will be a very modest increase over the LS7. Probably 520-530hp. More likely we'll probably get a boosted 600-650hp variant. Or if GM decides they like having 3 price points, two boosted variants. Probably a 550-575hp and 650+hp model.

I hope you are wrong, there needs to be a 575-600hp NA car that can be tracked without heat soak issues and the extra weight of FI. If they don't build a bunch of them it wont have to meet the cafe BS rules.

I hope you are wrong, there needs to be a 575-600hp NA car that can be tracked without heat soak issues and the extra weight of FI. If they don't build a bunch of them it wont have to meet the cafe BS rules.

I hope you are wrong, there needs to be a 575-600hp NA car that can be tracked without heat soak issues and the extra weight of FI. If they don't build a bunch of them it wont have to meet the cafe BS rules.

Track-focused, light-weight, and with a 550HP tuned 6.2L LT1 is more likely. But not introduced as soon as people think.

With the first year of the C7R running the old LS engine until they have more time to develop a new LT-based racing engine, why would GM introduce a new C7Z06 until they could claim it featured a new C7R LT engine from the track? So I doubt will see it at the 2014 NAIAS...

I'd love to see it, but I doubt we'll get it. The C7 shows plainly the focus on meeting EPA standards. The equation for more HP in an NA application has been the same for a very long time. A larger camshaft for more air and fuel, better heads to move the air and finally a better flowing exhaust to let it out. The larger camshaft causes issues with emissions and, if large enough, driveability. Consumption will be higher even when not driving aggressively because the valve events will require it.

If we do see a bigger displacement LTx, it will probably be a very mild bump over the LS7 for these reasons. There's no magic wand that is going to make a cam capable of supporting 600+hp be civil enough to market to general public. Even if they could get past the emissions issues.

FI doesn't have a lot of these problems. You don't need a large camshaft, just one patterned for boost. Consumption is comparable when not making boost. Hitting your target output isn't all that difficult. I just wish we would see low mounted turbos from an efficiency and weight balance perspective.

So my guess is if we do see a larger LTx motor it will be a very modest increase over the LS7. Probably 520-530hp. More likely we'll probably get a boosted 600-650hp variant. Or if GM decides they like having 3 price points, two boosted variants. Probably a 550-575hp and 650+hp model.

A ZR1 doesn't get anywhere near the mileage of the LS7 even just cruising at 75 on the highway. If GM made two supercharged variants then no one would buy the more expensive one - because they know they can save $25k buy the cheaper on and just pulley the car down to make the same or more power safely as the far more expensive model. Most people would far prefer an NA car for track use over a blown car too, because it is far easier to go fast in one on most tracks which are tighter with less long straightaways.

And as far as consumption an LS7 with AFM could well reach 27-28MPG on the highway - something not even remotely close to a blown LT1, and it would probably weight no more than the LT1. Since GM cares so much about fuel economy now why would they do this? The only way almost anyone would be motived to buy the more expensive blown variant if there were two is if it was twin turbo, because the car would have near unlimited potential for power.

A ZR1 doesn't get anywhere near the mileage of the LS7 even just cruising at 75 on the highway. If GM made two supercharged variants then no one would buy the more expensive one - because they know they can save $25k buy the cheaper on and just pulley the car down to make the same or more power safely as the far more expensive model. Most people would far prefer an NA car for track use over a blown car too, because it is far easier to go fast in one on most tracks which are tighter with less long straightaways.

And as far as consumption an LS7 with AFM could well reach 27-28MPG on the highway - something not even remotely close to a blown LT1, and it would probably weight no more than the LT1. Since GM cares so much about fuel economy now why would they do this? The only way almost anyone would be motived to buy the more expensive blown variant if there were two is if it was twin turbo, because the car would have near unlimited potential for power.

The ZR1 has greater output and different gearing. As I said I would love to see a high output NA variant, but I doubt it will happen. I don't disagree that a mildly tweaked 7.0L LTx variant would return decent economy. But the 575-600hp figures people keep throwing around will necessitate a much bigger cam. better heads and very efficient exhaust. That will make it much harder to hit the driveability and efficiency targets.

With equal gearing a blown motor will return better efficiency. When it's not making boost, it's essentially a NA motor with a lot smaller cam. Blower motors generally have a more conservative (rich) fuel map, so consumption goes up slightly. But it's not close to what a larger cam in the NA motor would consume. My friends A&A C5 making 720hp gets comparable mileage to my ~500hp LS1 with a H/C combo. It's much easier to drive (almost stock like).

You would probably have more than just output differentiating 2 blown models. But even so, people would still buy the top model. Sure the output wouldn't be enough to justify the cost to a DIY type. But that's always been the case. A Z06 with a blower and the right options would outrun a ZR1, but the audience that goes for the ZR1 wants the warranty and polish that goes along with the factory package.

Again I am not against a high output NA motor. I would love it if they did it. I'm just saying that the FI motor route seems to fit GM's current trend with the C7.